Graphical interchange format
Hard g right?
No
If that were always the case then instead of Nasuh (NASA) it would be pronounced Nehsah. (That one isn't to prove it's jif, it's to disprove the main gif argument.)
(I always thought this argument is more deciding.) The person who invented them says jif.
I really don't want to force people to change, but I'm just going to keep saying it the correct way.